[PATCH] Evdev: Fix bug in checking duplicate clock change request

[PATCH] Evdev: Fix bug in checking duplicate clock change request

[Aniroop Mathur]

From: Aniroop Mathur <a.mathur@samsung.com>

clk_type and clkid stores different predefined clock identification
values so they cannot be compared for checking duplicate clock change
request. Therefore, lets fix it to avoid unexpected results.

Signed-off-by: Aniroop Mathur <a.mathur@samsung.com>
Signed-off-by: Aniroop Mathur <aniroop.mathur@gmail.com>
---
 drivers/input/evdev.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c
index 08d4964..0d40f6f 100644
--- a/drivers/input/evdev.c
+++ b/drivers/input/evdev.c
@@ -56,7 +56,7 @@ struct evdev_client {
 	struct fasync_struct *fasync;
 	struct evdev *evdev;
 	struct list_head node;
-	int clk_type;
+	unsigned int clk_type;
 	bool revoked;
 	unsigned int bufsize;
 	struct input_event buffer[];
@@ -146,9 +146,7 @@ static void evdev_queue_syn_dropped(struct evdev_client *client)
 static int evdev_set_clk_type(struct evdev_client *client, unsigned int clkid)
 {
 	unsigned long flags;
-
-	if (client->clk_type == clkid)
-		return 0;
+	unsigned int prev_clk_type = client->clk_type;
 
 	switch (clkid) {
 
@@ -165,6 +163,10 @@ static int evdev_set_clk_type(struct evdev_client *client, unsigned int clkid)
 		return -EINVAL;
 	}
 
+	/* No need to flush if clk_type is same as before */
+	if (client->clk_type == prev_clk_type)
+		return 0;
+
 	/*
 	 * Flush pending events and queue SYN_DROPPED event,
 	 * but only if the queue is not empty.
-- 
2.6.2

Re: [PATCH] Evdev: Fix bug in checking duplicate clock change request

[Dmitry Torokhov]

Hi Aniroop,

On Thu, Oct 29, 2015 at 01:38:32AM +0530, Aniroop Mathur wrote:
> From: Aniroop Mathur <a.mathur@samsung.com>
> 
> clk_type and clkid stores different predefined clock identification
> values so they cannot be compared for checking duplicate clock change
> request. Therefore, lets fix it to avoid unexpected results.

Good catch!

> 
> Signed-off-by: Aniroop Mathur <a.mathur@samsung.com>
> Signed-off-by: Aniroop Mathur <aniroop.mathur@gmail.com>

You only need one signoff, which one should I keep? The Samsung one?

> ---
>  drivers/input/evdev.c | 10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c
> index 08d4964..0d40f6f 100644
> --- a/drivers/input/evdev.c
> +++ b/drivers/input/evdev.c
> @@ -56,7 +56,7 @@ struct evdev_client {
>  	struct fasync_struct *fasync;
>  	struct evdev *evdev;
>  	struct list_head node;
> -	int clk_type;
> +	unsigned int clk_type;
>  	bool revoked;
>  	unsigned int bufsize;
>  	struct input_event buffer[];
> @@ -146,9 +146,7 @@ static void evdev_queue_syn_dropped(struct evdev_client *client)
>  static int evdev_set_clk_type(struct evdev_client *client, unsigned int clkid)
>  {
>  	unsigned long flags;
> -
> -	if (client->clk_type == clkid)
> -		return 0;
> +	unsigned int prev_clk_type = client->clk_type;

I prefer the other way around: convert to a temp and then compare. I;ll
fix it up on my side.

>  
>  	switch (clkid) {
>  
> @@ -165,6 +163,10 @@ static int evdev_set_clk_type(struct evdev_client *client, unsigned int clkid)
>  		return -EINVAL;
>  	}
>  
> +	/* No need to flush if clk_type is same as before */
> +	if (client->clk_type == prev_clk_type)
> +		return 0;
> +
>  	/*
>  	 * Flush pending events and queue SYN_DROPPED event,
>  	 * but only if the queue is not empty.
> -- 
> 2.6.2
> 

Thanks.

-- 
Dmitry

Re: [PATCH] Evdev: Fix bug in checking duplicate clock change request

[Aniroop Mathur]

Hello Mr. Torokhov,

On Fri, Oct 30, 2015 at 4:45 PM, Dmitry Torokhov
<dmitry.torokhov@gmail.com> wrote:
> Hi Aniroop,
>
> On Thu, Oct 29, 2015 at 01:38:32AM +0530, Aniroop Mathur wrote:
>> From: Aniroop Mathur <a.mathur@samsung.com>
>>
>> clk_type and clkid stores different predefined clock identification
>> values so they cannot be compared for checking duplicate clock change
>> request. Therefore, lets fix it to avoid unexpected results.
>
> Good catch!
>

Thank you :)

>>
>> Signed-off-by: Aniroop Mathur <a.mathur@samsung.com>
>> Signed-off-by: Aniroop Mathur <aniroop.mathur@gmail.com>
>
> You only need one signoff, which one should I keep? The Samsung one?
>

Yes, Samsung one.

>> ---
>>  drivers/input/evdev.c | 10 ++++++----
>>  1 file changed, 6 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c
>> index 08d4964..0d40f6f 100644
>> --- a/drivers/input/evdev.c
>> +++ b/drivers/input/evdev.c
>> @@ -56,7 +56,7 @@ struct evdev_client {
>>       struct fasync_struct *fasync;
>>       struct evdev *evdev;
>>       struct list_head node;
>> -     int clk_type;
>> +     unsigned int clk_type;
>>       bool revoked;
>>       unsigned int bufsize;
>>       struct input_event buffer[];
>> @@ -146,9 +146,7 @@ static void evdev_queue_syn_dropped(struct evdev_client *client)
>>  static int evdev_set_clk_type(struct evdev_client *client, unsigned int clkid)
>>  {
>>       unsigned long flags;
>> -
>> -     if (client->clk_type == clkid)
>> -             return 0;
>> +     unsigned int prev_clk_type = client->clk_type;
>
> I prefer the other way around: convert to a temp and then compare. I;ll
> fix it up on my side.
>

I thought that was the only better way of all.
I am not sure what exactly you're referring. I guess I need little
more elaboration here or anyways, I'll check it up up once you apply
it.

>>
>>       switch (clkid) {
>>
>> @@ -165,6 +163,10 @@ static int evdev_set_clk_type(struct evdev_client *client, unsigned int clkid)
>>               return -EINVAL;
>>       }
>>
>> +     /* No need to flush if clk_type is same as before */
>> +     if (client->clk_type == prev_clk_type)
>> +             return 0;
>> +
>>       /*
>>        * Flush pending events and queue SYN_DROPPED event,
>>        * but only if the queue is not empty.
>> --
>> 2.6.2
>>
>
> Thanks.
>
> --
> Dmitry

Regards,
Aniroop

Re: [PATCH] Evdev: Fix bug in checking duplicate clock change request

[Aniroop Mathur]

On Fri, Oct 30, 2015 at 6:34 PM, Aniroop Mathur
<aniroop.mathur@gmail.com> wrote:
>
> Hello Mr. Torokhov,
>
> On Fri, Oct 30, 2015 at 4:45 PM, Dmitry Torokhov
> <dmitry.torokhov@gmail.com> wrote:
> > Hi Aniroop,
> >
> > On Thu, Oct 29, 2015 at 01:38:32AM +0530, Aniroop Mathur wrote:
> >> From: Aniroop Mathur <a.mathur@samsung.com>
> >>
> >> clk_type and clkid stores different predefined clock identification
> >> values so they cannot be compared for checking duplicate clock change
> >> request. Therefore, lets fix it to avoid unexpected results.
> >
> > Good catch!
> >
>
> Thank you :)
>
> >>
> >> Signed-off-by: Aniroop Mathur <a.mathur@samsung.com>
> >> Signed-off-by: Aniroop Mathur <aniroop.mathur@gmail.com>
> >
> > You only need one signoff, which one should I keep? The Samsung one?
> >
>
> Yes, Samsung one.
>
> >> ---
> >>  drivers/input/evdev.c | 10 ++++++----
> >>  1 file changed, 6 insertions(+), 4 deletions(-)
> >>
> >> diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c
> >> index 08d4964..0d40f6f 100644
> >> --- a/drivers/input/evdev.c
> >> +++ b/drivers/input/evdev.c
> >> @@ -56,7 +56,7 @@ struct evdev_client {
> >>       struct fasync_struct *fasync;
> >>       struct evdev *evdev;
> >>       struct list_head node;
> >> -     int clk_type;
> >> +     unsigned int clk_type;
> >>       bool revoked;
> >>       unsigned int bufsize;
> >>       struct input_event buffer[];
> >> @@ -146,9 +146,7 @@ static void evdev_queue_syn_dropped(struct evdev_client *client)
> >>  static int evdev_set_clk_type(struct evdev_client *client, unsigned int clkid)
> >>  {
> >>       unsigned long flags;
> >> -
> >> -     if (client->clk_type == clkid)
> >> -             return 0;
> >> +     unsigned int prev_clk_type = client->clk_type;
> >
> > I prefer the other way around: convert to a temp and then compare. I;ll
> > fix it up on my side.
> >
>
> I thought that was the only better way of all.
> I am not sure what exactly you're referring. I guess I need little
> more elaboration here or anyways, I'll check it up up once you apply
> it.

Ahhh okay... I got the other way around.
(Filling client->clk_type in the end instead)

>
>
>
> >>
> >>       switch (clkid) {
> >>
> >> @@ -165,6 +163,10 @@ static int evdev_set_clk_type(struct evdev_client *client, unsigned int clkid)
> >>               return -EINVAL;
> >>       }
> >>
> >> +     /* No need to flush if clk_type is same as before */
> >> +     if (client->clk_type == prev_clk_type)
> >> +             return 0;
> >> +
> >>       /*
> >>        * Flush pending events and queue SYN_DROPPED event,
> >>        * but only if the queue is not empty.
> >> --
> >> 2.6.2
> >>
> >
> > Thanks.
> >
> > --
> > Dmitry
>
> Regards,
> Aniroop